Method of Authenticating a Device to Access a Service

1. A method comprising: authenticating a user of a first device while accessing a service offered by a service provider, the first device forming part of a group of devices in a local network that includes a second device of the user having an identification module for identifying and authenticating the user with the service, wherein authenticating a user comprises: a prior broadcast step during which the second device broadcasts to the first device its ability to supply proof of an authentication; and, when the first device seeks to authenticate itself, the method further comprises: a request step of the first device requesting the second device for proof of successful authentication with the service, the proof including an identity of the user of the second device; a transmission step of the second device transmitting the proof to the first device; and an authentication step of authenticating the user of the first device with the service on the basis of the received proof using the first device.

2. A method according to claim 1 , wherein the method includes a prior identification step of identifying at least one device of the group that is suitable for supplying proof.

3. A non-transitory computer-readable medium comprising a computer program stored thereon, which includes instructions for performing a method, when the program is executed by a processor, the method comprising: authenticating a user of a first device while accessing a service offered by a service provider, wherein the first device forms part of a group of devices in a local network that includes a second device of the user having an identification module for identifying and authenticating the user with the service, wherein authenticating a user comprises: a prior broadcasting during which the second device broadcasts to the first device its ability to supply proof of an authentication; and, when the first device seeks to authenticate itself, the method further comprises: the second device receiving a request from the first device requesting the second device for proof of successful authentication with the service, the proof including an identity of the user of the second device; a transmission step of the second device transmitting the proof to the first device; and an authentication step of authenticating the user of the first device with the service on the basis of the received proof using the first device.

4. A first device comprising: a communications module configured to communicate with a communications network and access a service suitable for being delivered by a service provider and to which access needs to be preceded by authentication; and a processor module including a hardware processor configured to receive from a second device of the user in a local network that includes the first device, a message indicating that the second device has the ability to supply proof of authentication; request proof from the second device; receive from the second device proof of successful authentication relating to a service; and authenticate with the service using the proof.

5. A computer system comprising: a local network comprising a first device of a user and a second device of the user; the first device comprising: a communications module configured to communicate with a communications network and access a service suitable for being delivered by a service provider and to which access needs to be preceded by authentication; and a processor module configured to: receive from the second device a message indicating that the second device has the ability to supply proof of authentication; request proof from the second device; and receive from the second device proof of successful authentication relating to a service; and the second device, which comprises: a communications module configured to communicate with the communications network and to access the service suitable for being delivered by the service provider and to which access needs to be preceded by authentication; a broadcast module configured to broadcast to other devices its ability to provide the proof of authentication; and a proof transmission module configured to, on request, transmit the proof of successful authentication relating to the service, the proof being sent to the first device in order to enable a user of the first device to be authenticated in order to access the service.